Well, the Hijri date 11 Dhul Qidah 1400 corresponds to the Gregorian date Saturday, 20 September 1980. This date lies in the eleventh month of the Hijri year 1400 AH, which is Dhu Al-Qidah of 1400 AH. Both this Hijri and Gregorian date occur on the single day that is Saturday without any doubt. The Arabic date 1400/11/11 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 20 September 1980 to its equivalent Arabic date.
The following is the conversion of the Arabic date 11 Dhul Qidah 1400 AH to its equivalent Gregorian date.
وَيَسْـَٔلُونَكَ عَنِ ٱلْجِبَالِ فَقُلْ يَنسِفُهَا رَبِّى نَسْفًۭا
They will ask thee of the mountains (on that day). Say: My Lord will break them into scattered dust.
Surah Taa-Haa(20:105)
Sahih al-Bukhari
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
Chapter: Hajjat-ul-Wada
Narrated `Aisha:
(the wife of the Prophet) Safiya bin Huyai, the wife of the Prophet (ﷺ) menstruated during Hajjat-ul- Wada` The Prophet (ﷺ) said, "Is she going to detain us?" I said to him, "She has already come to Mecca and performed the Tawaf (ul-ifada) around the Ka`ba, O Allah's Messenger (ﷺ)." The Prophet (ﷺ) said, " Let her then proceed on (to Medina).
Sahih al-Bukhari 4401